Accession Number : ADA289723

Title :   Chronic Physiological Effects Of Positive Pressure Breathing In A High Sustained G Environment.

Descriptive Note : Final rept. Dec 91-Jun 93,

Corporate Author : SYSTEMS RESEARCH LABS INC DAYTON OH

Personal Author(s) : Tripp, Lloyd D., Jr. ; Bolia, Steve ; Cooper, James ; Albery, William B. ; Marit, Gary B.

PDF Url : ADA289723

Report Date : JAN 1993

Pagination or Media Count : 41

Abstract : A new Positive Pressure Breathing system for G protection (PBG) known as COMBAT EDGE, is currently being evaluated for both USAF and NAVY F-16 and F-15 aircraft. This system is being used in conjunction with the current Air Force standard CSU-13B/P anti-G suit. Once this system is fully deployed, pilots can be exposed to a high time duration dose of positive pressure breathing over the course of a 20 year flying career. Recent concerns in this area have been raised by the Aerospace Medical Community as to the possibility of occupational hazards associated with long duration exposure to PPB. This study addresses those questions by studying both the physiological and histopathological effects of long duration exposure to PPB. In this study, four, protected Minihanford miniature swine were exposed over 27 days to 10 minute exposures of continuous high sustained acceleration on a 20.5 ft. radius centrifuge. Two-dimensional echocardiograms were accomplished prior to G exposure and again after the exposure at day 27. In addition, aortic pulmonary pressure, respiration, heart rate, and cardiac output data were collected on experimental test day 1 and 27. Necropsy and subsequent histopathological examinations of major organs were accomplished. This study found no significant pathophysiological changes which could be attributed to the chronic exposure to PPB.

Descriptors :   *PROTECTIVE EQUIPMENT, *PRESSURE BREATHING, OUTPUT, TIME INTERVALS, WARFARE, AIR FORCE, EXPOSURE(GENERAL), TWO DIMENSIONAL, EDGES, PILOTS, CENTRIFUGES, LONG RANGE(TIME), CAREERS, AEROSPACE SYSTEMS, FLIGHT, PHYSIOLOGICAL EFFECTS, DOSAGE, STANDARDS, LUNG, PHYSIOLOGY, G SUITS, PATHOLOGY, RESPIRATION, HEART RATE, MINIATURIZATION, HEART, HIGH ACCELERATION, RADIUS(MEASURE), AEROSPACE MEDICINE, AUTOPSY, HISTOPATHOLOGY, AORTA, ORGANS(ANATOMY), ECHOCARDIOGRAPHY, SWINE.

Subject Categories : Life Support Systems
      Stress Physiology
      Protective Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE